Another BBC Motor??? Dampers
 

Have another engine question – Not to make this to long of post but the motor I have appears to be a 468 with an aftermarket forged crank and H-Beam rods. When I started to tear the truck down and I removed the flywheel I noticed it had no external weight on it like a normal 454, once I found out that it had a aftermarket crank I assumed this was OK it was just an internally balanced assembly (I am only assuming this as I really don’t know how to tell???? The front damper looked weird to me also, but I just figured it was a smaller aftermarket damper BUT a buddy was over the other night and started looking at it and said it was just a stock damper that someone took the outer portion off of. The damper has no timing marks on the outside and also has no external weight?? He stated I need to get a new damper. Would I get a damper for an externally balanced motor? Or does it even matter???

I will post pics of the damper tonight when I get back to my home computer but any additional help before then would be great

Thanks guys

Re: Another BBC Motor??? Dampers
 

No one??

Re: Another BBC Motor??? Dampers
 

Sounds like it would be internaly balanced . If it were mine I would find a damper without a weight to try . I had the same problem one time and had the wrong flexplate so it shook like hell . The motor should tell you if its right or not .

Re: Another BBC Motor??? Dampers
 

Has anyone used a Professional Products damper??

Re: Another BBC Motor??? Dampers
 

The PP dampers are crap,if your looking for a reasonably priced SFI damper try Pioneer or Probond or Summit

Re: Another BBC Motor??? Dampers
 

If it's in your budget I would get an ATI external, and if your motor is internal you can unbolt the weight. It's like havin two balancer's in one. Look on racin junk.com It's full of good used ones. It's hard to go wrong buying a used balancer!

Re: Another BBC Motor??? Dampers
 

Was talking to a guy the other day and when he looked at my motor he said the aftermarket crank has the weight on the back of it, so I am still confused if I have an externally balanced motor or if it is internally. Is there any way I can tell for sure before I put the wrong damper on. I will try and find a pic of the damper that came off it, but it looks like a stock one without the outside rubber part. I can get a ATI blem damper for $200 straight from ATI (only has sractches nothing structurally wrong) jsut need to know which one.

Re: Another BBC Motor??? Dampers
 

Heres a pic of the damper that was on the motor

Re: Another BBC Motor??? Dampers
 

Back of Crank

Re: Another BBC Motor??? Dampers
 

No help guys??

Talked to ATI and they told me while you can remove the weight on their external balancer to turn it into a internal balancer that do not recommend it. He told me I need to figure out what I have then order the proper balancer?????????

HELP

Re: Another BBC Motor??? Dampers
 

While I can't help a bit with making a ID on what you have there, I will agree with the phone jocky at ATI. You better haul the thing down to your local machinist and have them check the balance. Guess wrong and your going to be wasting $'s. The ATI balancers are made 'tight' and have to be honed to a perfect press fit for YOUR crank. Which means your going to own it even if it is the wrong one.

Re: Another BBC Motor??? Dampers
 

Wow Marv, so since teh motor just got put back in the truck how in the world am I going to hone the balancer to get it to fit perfectly?? Isn't thte crank snout the same on all bbc cranks. Why would they make it so difficult. Do all aftermarket balancers have to have this done to them?

Re: Another BBC Motor??? Dampers
 

Because all cranks have a 'slight' variation. I have a ATI superdamper that was honed and fit to a Cola crank. I have a Eagle sbc crank that you can push 'that' balancer on by hand,,, literally BY HAND! ATI leaves them tight so they can be honed to the exact press fit for THAT crank. (off the top of my head) they want a 0.0002 to 0.0007 press fit to properly absorb harmonics from the crank. Too tight and you can't get it on the snout, too loose and it doesn't do it's job,,, absorb harmonics. And No, not all aftermarket dampers need to be honed to fit,,, just the good ones.

In all honesty, if you have a GM crank you will probably be just fine having it honed to /normal/ GM crank size. But if you have some imported POS crank final machined anywhere else other than the US,, it's a crap shoot. If you have a 'good' mic and know how to use it, you can just tell your machinist what the diameter is, and what the press-fit needs to be (will be in the instructions with the damper)